initial work on scrollable divs

src/main.c3

@@ -51,10 +51,10 @@ fn int main(String[] args)
 		ctx.frame_begin()!!;
 
 		// main div, fill the whole window
-		ctx.div_begin("main", ugui::DIV_FILL)!!;
+		ctx.div_begin("main", ugui::Rect{.w=ctx.width/2})!!;
 		{|
 			ctx.layout_set_column()!!;
-			if (ctx.button("button0", ugui::Rect{100,100,30,30})!!.mouse_press) {
+			if (ctx.button("button0", ugui::Rect{0,0,30,30})!!.mouse_press) {
 				io::printn("press button0");
 			}
 			ctx.layout_next_column()!!;
@@ -72,6 +72,15 @@ fn int main(String[] args)
 		|};
 		ctx.div_end()!!;
 
+		ctx.div_begin("second", ugui::DIV_FILL)!!;
+		{|
+			if (ctx.slider_ver("slider_other", ugui::Rect{0,0,30,100})!!.update) {
+				ugui::Elem* e = ctx.get_elem_by_label("slider_other")!!;
+				io::printfn("other slider: %f", e.slider.value);
+			}
+		|};
+		ctx.div_end()!!;
+
 		ctx.frame_end()!!;
 		/* End UI Handling */
 

src/ugui_data.c3

@@ -192,3 +192,19 @@ macro point_in_rect(Point p, Rect r)
 {
 	return (p.x >= r.x && p.x <= r.x + r.w) && (p.y >= r.y && p.y <= r.y + r.h);
 }
+
+// return true if rect a contains b
+macro rect_contains(Rect a, Rect b)
+{
+    return (a.x <= b.x && a.y <= b.y && a.x+a.w >= b.x+b.w && a.y+a.h >= b.y+b.h);
+}
+
+macro rect_intersection(Rect a, Rect b)
+{
+    return Rect{
+        .x = (short)max(a.x, b.x),
+        .y = (short)max(a.y, b.y),
+        .w = (short)min(a.x+a.w, b.x+b.w) - (short)max(a.x, b.x),
+        .h = (short)min(a.y+a.h, b.y+b.h) - (short)max(a.y, b.y),
+    };
+}

src/ugui_div.c3

@@ -0,0 +1,64 @@
+module ugui;
+
+
+fn void! Ctx.div_begin(&ctx, String label, Rect size)
+{
+	Id id = hash(label);
+
+	Elem *parent = ctx.get_parent()!;
+	Elem* c_elem = ctx.get_elem(id)!;
+	isz div_node = ctx.tree.add(id, ctx.active_div)!;
+	ctx.active_div = div_node;
+
+	// 1. Fill the element fields
+	c_elem.type  = ETYPE_DIV;
+
+	// do layout and update flags only if the element was updated
+	if (c_elem.flags.is_new || parent.flags.updated) {
+		// 2. layout the element
+		c_elem.bounds = ctx.position_element(parent, size);
+
+		// 3. Mark the element as updated
+		c_elem.flags.updated = true;
+		// 4. Fill the div fields
+		c_elem.div.layout   = parent.div.layout;
+		c_elem.div.origin_c = Point{
+		    .x = c_elem.bounds.x,
+		    .y = c_elem.bounds.y,
+		};
+		c_elem.div.color_bg = uint_to_rgba(0xff0000ff);
+		c_elem.div.origin_r = c_elem.div.origin_c;
+	}
+
+	// Add the background to the draw stack
+	Cmd cmd = {
+	    .type = CMD_RECT,
+	    .rect = {
+		    .rect  = c_elem.bounds,
+		    .color = c_elem.div.color_bg,
+		},
+	};
+	ctx.cmd_queue.enqueue(&cmd)!;
+
+	// TODO: check active
+	// TODO: check resizeable
+
+	// TODO: check scrollbars
+	// if the bounds are outside of the view then allocate space for scrollbars
+	DivLayout old_layout = c_elem.div.layout;
+	c_elem.div.layout = LAYOUT_FLOATING;
+	c_elem.div.layout = old_layout;
+
+	if (parent.flags.has_focus) {
+		if (point_in_rect(ctx.input.mouse.pos, c_elem.bounds)) {
+			c_elem.flags.has_focus = true;
+		}
+	}
+
+}
+
+fn void! Ctx.div_end(&ctx)
+{
+	// the active_div returns to the parent of the current one
+	ctx.active_div = ctx.tree.parentof(ctx.active_div)!;
+}

src/ugui_impl.c3

@@ -81,7 +81,7 @@ fn void! Ctx.frame_begin(&ctx)
                 .h = ctx.height,
             },
             .div = {
-                .layout   = LAYOUT_ROW,
+                .layout = LAYOUT_ROW,
             },
             .flags = c_elem.flags,
         };
@@ -120,60 +120,6 @@ $if 1:
 $endif
 }
 
-fn void! Ctx.div_begin(&ctx, String label, Rect size)
-{
-	Id id = hash(label);
-
-	Elem *parent = ctx.get_parent()!;
-	Elem* c_elem = ctx.get_elem(id)!;
-	isz div_node = ctx.tree.add(id, ctx.active_div)!;
-	ctx.active_div = div_node;
-
-	// 1. Fill the element fields
-	c_elem.type  = ETYPE_DIV;
-
-	// do layout and update flags only if the element was updated
-	if (c_elem.flags.is_new || parent.flags.updated) {
-		// 2. layout the element
-		c_elem.bounds = ctx.position_element(parent, size);
-
-		// 3. Mark the element as updated
-		c_elem.flags.updated = true;
-		// 4. Fill the div fields
-		c_elem.div.layout   = parent.div.layout;
-		c_elem.div.origin_c = Point{
-		    .x = c_elem.bounds.x,
-		    .y = c_elem.bounds.y,
-		};
-		c_elem.div.color_bg = uint_to_rgba(0xff0000ff);
-		c_elem.div.origin_r = c_elem.div.origin_c;
-	} else if (parent.flags.has_focus) {
-		if (point_in_rect(ctx.input.mouse.pos, c_elem.bounds)) {
-			c_elem.flags.has_focus = true;
-		}
-	} else {
-		// TODO: check active
-		// TODO: check scrollbars
-		// TODO: check resizeable
-	}
-
-	// Add the background to the draw stack
-	Cmd cmd = {
-	    .type = CMD_RECT,
-	    .rect = {
-		    .rect  = c_elem.bounds,
-		    .color = c_elem.div.color_bg,
-		},
-	};
-	ctx.cmd_queue.enqueue(&cmd)!;
-}
-
-fn void! Ctx.div_end(&ctx)
-{
-	// the active_div returns to the parent of the current one
-	ctx.active_div = ctx.tree.parentof(ctx.active_div)!;
-}
-
 /**
  * @ensure elem != null
 **/

src/ugui_layout.c3

@@ -77,7 +77,7 @@ fn void! Ctx.layout_next_column(&ctx)
 // position the rectangle inside the parent according to the layout
 fn Rect Ctx.position_element(&ctx, Elem *parent, Rect rect, bool style = false)
 {
-	Rect  elem_rect;
+	Rect  bounds;
 	Point origin;
 
 	// 1. Select the right origin
@@ -92,30 +92,29 @@ fn Rect Ctx.position_element(&ctx, Elem *parent, Rect rect, bool style = false)
 	}
 
 	// 2. Position the rect
-	elem_rect.x = origin.x + rect.x;
+	bounds.x = (short)max(origin.x + rect.x, 0);
-	elem_rect.y = origin.y + rect.y;
+	bounds.y = (short)max(origin.y + rect.y, 0);
 
 	// 3. Calculate width & height
-	// TODO: what about negative values?
 	// FIXME: account for origin offset!!
-	elem_rect.w = rect.w > 0 ? rect.w : parent.bounds.w;
+	bounds.w = rect.w > 0 ? rect.w : parent.bounds.w;
-	elem_rect.h = rect.h > 0 ? rect.h : parent.bounds.h;
+	bounds.h = rect.h > 0 ? rect.h : parent.bounds.h;
 
 	// 4. Update the origins of the parent
 	parent.div.origin_r = Point{
-	    .x = elem_rect.x + elem_rect.w,
+	    .x = bounds.x + bounds.w,
-	    .y = elem_rect.y,
+	    .y = bounds.y,
 	};
 	parent.div.origin_c = Point{
-	    .x = elem_rect.x,
+	    .x = bounds.x,
-	    .y = elem_rect.y + elem_rect.h,
+	    .y = bounds.y + bounds.h,
 	};
 
 	// if using the style then apply margins
 	// FIXME: this does not work
 	if (style && parent.div.layout != LAYOUT_FLOATING) {
-		elem_rect.x += ctx.style.margin.x;
+		bounds.x += ctx.style.margin.x;
-		elem_rect.y += ctx.style.margin.y;
+		bounds.y += ctx.style.margin.y;
 
 		// total keep-out borders
 		Rect margin_tot = {
@@ -136,18 +135,5 @@ fn Rect Ctx.position_element(&ctx, Elem *parent, Rect rect, bool style = false)
 		parent.div.origin_c.y += margin_tot.y + margin_tot.h;
 	}
 
-	/*
+	return bounds;
-	        printf(
-	            "positioning rect: %lx {%d %d %d %d}(%d %d %d %d) . {%d %d %d
-	   %d}\n", parent.id, rect.x, rect.y, rect.w, rect.h, parent.bounds.x,
-	            parent.bounds.y,
-	            parent.bounds.w,
-	            parent.bounds.h,
-	            elem_rect.x,
-	            elem_rect.y,
-	            elem_rect.w,
-	            elem_rect.h
-	        );
-	*/
-	return elem_rect;
 }